Brain injury frequently results in cognitive impairment reducing an individual?s ability to judge driving situations accurately. Rehabilitation professionals use on-road tests to determine if an individual is safe to drive, but these tests are typically performed under calm conditions and offer little information on the individual?s responses to typical, real-life driving challenges. STISIM is a relatively low-cost, high performance, customizable driving simulator based upon standard desktop computer technology. The purpose of this Phase II STTR project is to determine if STISIM can be adapted to the clinical rehabilitation market for use by rehabilitation driving professionals and their client with cognitive impairments. Proof of concept was demonstrated in Phase I which resulted in the creation of a driving scenario that offers increasingly complex driving challenges as the route proceeds, the development of data collection and analysis procedures to quantitatively evaluate driving performance and the pilot testing of the scenario, data collection and processing methods using five subjects with mild cognitive impairments and five age-matched control subjects with no impairments. The result demonstrated that the simulator was capable of identifying significant driving differences between the two groups. In Phase II, impairments to the hardware and software of STISIM will be implemented. A multi-center clinical study will be conducted to evaluate test-retest reliability, discriminant validity and concurrent validity of STISIM when using subjects with cognitive impairments. In addition, an ease-of-use study and a self-awareness pilot study will be conducted. At the end of Phase II, the applicant company (STI) will be prepared to move into a commercialization phase to bring the STISIM simulator into the rehabilitation market.